You have to establish a pack order ... a hierarchy in other words. Where you and your kids are at the top of the food chain and he is at the bottom. The best way to do that is at feeding times. Let your children put the food down to feed him, and then every few moments get them to pick the bowl calmly up again. Gator cant' have the bowl back until the children decide ... and if Gator follows the "sit" command then you can help them with it. Gator doesn't get the bowl back until he sits .... and you can do this as often as you like. That should help develop the chain of command. It doesn't sound as if Gator was being mean or vicious, just that he got over excited. Unfortunately, a child shouting and screaming in a high pitched voice can just come across as excited encouragement to a dog that is already in full play mode!!